bug report : multi panels docking together, mouse resize not work

MainWindow::MainWindow(QWidget *parent)
    : RdfRibbonMainWindow(parent)
    , ui(new Ui::MainWindow)
    {
    setCustomStyle("Office2010Blue");
    qApp->installEventFilter(this);

    createDockMainWindow();
    //createNormalDockMainWindow();
    createRibbon();
    createMdiDocumentExample();
   }

void MainWindow::createRibbon()
{
    RibbonPage* pageButtons = ribbonBar()->addPage(QStringLiteral("&主页"));
    QMenu* splitPopup = new QMenu(this);
    splitPopup->addAction(tr("Option 1"));
    splitPopup->addAction(tr("Option 2"));
    splitPopup->addAction(tr("Option 3"));

    RibbonGroup* groupClipboard = pageButtons->addGroup(tr("Clipboard"));
    QMenu* editPaste = new QMenu(this);
    QAction* actionPaste1 = editPaste->addAction(QIcon(":/res/smallClipboard.png"), tr("Paste"));
    actionPaste1->setPriority(QAction::LowPriority);
    actionPaste1->setShortcut(QKeySequence::Paste);

    QAction* actionPaste2 = groupClipboard->addAction(QIcon(":/res/clipboard.png"),
        tr("&Paste"), Qt::ToolButtonTextUnderIcon, editPaste);
    actionPaste2->setPriority(QAction::LowPriority);
    actionPaste2->setShortcut(QKeySequence::Paste);

    QAction* actionCut = groupClipboard->addAction(QIcon(":/res/smallCut.png"),
        tr("&Cut"), Qt::ToolButtonTextBesideIcon);
    actionCut->setShortcut(QKeySequence::Cut);

    QAction* actionCopy = groupClipboard->addAction(QIcon(":/res/smallCopy.png"),
        tr("&Copy"), Qt::ToolButtonTextBesideIcon);
    actionCopy->setShortcut(QKeySequence::Copy);

    groupClipboard->addAction(QIcon(":/res/smallFormatPainter.png"),
        tr("F&ormat Pointer"), Qt::ToolButtonTextBesideIcon);
    groupClipboard->setEnabled(false);

    RibbonGroup* groupView = pageButtons->addGroup(QStringLiteral("窗口"));
    QCheckBox* checkStatusBar = new QCheckBox(tr("Status Bar"));
    checkStatusBar->setToolTip(tr("CheckBox 1"));
    checkStatusBar->setCheckState(Qt::Checked);
    groupView->addWidget(checkStatusBar);
    connect(checkStatusBar, SIGNAL(stateChanged(int)), this, SLOT(hideStatusBar(int)));

    ribbonBar()->addPage(QStringLiteral("&模型"));
    ribbonBar()->addPage(QStringLiteral("&显示"))->setContextColor(ContextColorGreen);
    ribbonBar()->setFrameThemeEnabled();
}

void MainWindow::createDockMainWindow()
{
   
    m_holder = new RdfDockMainWindow(this);
    m_holder->setAttribute(Qt::WA_CanHostQMdiSubWindowTitleBar);

    m_holder->dockPanelManager()->setDockPanelTransparentWhileDragging(true);
    m_holder->dockPanelManager()->setArrowMarkersShown(true);
    m_holder->dockPanelManager()->setDockPanelFullContentsWhileDraggingShown(true);
    m_holder->dockPanelManager()->centralLayoutPanel();
    //mdiArea = new MdiArea(m_holder);


    
    mdiArea = new MdiArea(m_holder);
    mdiArea->setLineWidth(3);
    mdiArea->setFrameShape(QFrame::Panel);
    mdiArea->setFrameShadow(QFrame::Sunken);
    mdiArea->setViewMode(QMdiArea::TabbedView);
    qApp->installEventFilter(this);
    mdiArea->setHorizontalScrollBarPolicy(Qt::ScrollBarAsNeeded);
    mdiArea->setVerticalScrollBarPolicy(Qt::ScrollBarAsNeeded);

   
    setCentralWidget(m_holder);
    m_holder->dockPanelManager()->setCentralWidget(mdiArea);
    m_holder->dockPanelManager()->centralWidget()->setFocus();
    m_holder->createDockPanels();
}